Liquid-fuel burner



w.-A. DOBLE, w. A. DOBLE, 1R., AND 1. A. DOBLE.l

LIQUID FUEL BURNER.

APPLICATIQN FILED APR. 3, 1917.

1,386,994, Patented Aug. 9, 1921.v

K l5" l/ VV. A. DOBLE w. A. 00a/.5 JR. j. J. f1. DOBLE,

THE/fi A TTORNE Y5 new and useful narran stares PAT'stur ortica.l

WILLIAM A. DOBLE; WILLIAM- A.DOBLE, Jn., AND Jomr A. DOBLE, or sANrnAN.

CISCO, CALIFORNIA, .ASSIGNORS TO DOBLE LABORATORIES, OF CALIFORNIA, A CORPORATION OF CALIIEOQELNIA;l

SAN FRANCISCO,

LIQUID-FUEL Lumina# Application mea April a,

To all whom t may concern:

Be it know'n that We, WILLIAM A. DOBLE, "WILLIAMx A. DOBLE, J r., and JOHN A. DOBLE, citizens ofthe United States, and residents ofthe city and county'of San Francisco and State of California have invented aicertain Liquid-Fuel' f Burner, of which the following 1s a specification.

The invention relates to a burner vfor liquid hydrocarbon fuels and is particularly adapted for use in connection with the boilers of steam propelled automobiles, domestic water heaters and comparable devices.

An object of the invention is to provide a liquid fuel burner which will produce perfeet combustion of the fuel.

A vfurther object of the invention is to provide means for igniting the fuel at the burner.

Another object of the invention is to provide means for'properly proportioning the amount/of fuel and air fed to the burner..

The invention possesses other advantageous features, some of which, with the foregoing, will be set forth at length in the following description, where we shall outline in full that-form of the invention which '.we have selected for illustration in the drawings accompanying and forming part of the resent specification. In said drawings,we ave shown one specific form of our generic 1nvention, but it is to be'understood that we do not limit ourselves to such form, because the invention as expressed in the claims may be embodied in a plurality of forms.

Referring to `sald drawings:

Figure l is a vertical section, partly dia-A grammatic, of one form of theburner of our invention.

F 1g. 2 is a cross sect1on of a modliied form of burner.

Fig. 3 is a cross section of a modified form of burner in which the air currentis produced by' a rotating element fromwhich the fuel is discharged.

The burner of our invention contains features which particularly adapt it for use in connection with. the 'boilers of steamdriven automobiles, domestic. water heaters and devices wherein gas is at present used as fuel. It produces a hot, clean flame in which the mixture of fuel and airis such that the flame will not attack the material of the boiler or other device in which it is used.4v

v Specification of Letters Patent.

'The burner is constructed so that a. large Patented Aug. e, 1921..`

1917. serial'No. 159,448. 4

amount of explosive mixture of air and fuel is not present, thereby eliminating backfiring and 1s so constructed that the flame doc s not vibrate,/thereby eliminating the whistling noise so common in prior burners.

It is also flexible in control, that is, the flame 'ceases assoon 'as the fuel isslut off and the fuel lgnites immediately after the fuel is 4turned on. The burner is also constructed/ so that 1t mayl be started on a light fuel and after it becomes heated, the vsu fuelmaly be cut of and heavy uel used. It 1s hlgh y important in liquid fuel burners ply off light wherein a mixture of air and fuel is dis i .charged 'by the burner, ,that the mixture ignite immediately as itbegins to emerge,.'

since otherwise, the boiler, waterheater or other device, becomes charged with a highly explosive mixture, which, when it ignites, explodes with destructive violence. also advantageous from an economical stand4 point, to be able to extinguish the flame immediately when it is no longer required.

It is" The burner'of our invention possesses all of these advantageous features.

In one of its embodiments the burner comprises an air chamber 2, preferablyannular in shape,l but which may be ofl any desiredshape, into which air is forced by a suitable blower orother device. For 'many uses-,- the annular burner is advantageous and We have illustrated, and will describe'. an annular burner, but it is to be understood that we do not limit ourselves to such form. The air inlet pipe 22 is preferably tangentially disposed with relation tothe air chamber, so

that the air is given a rotary motion in the chamber equally distributing the fuel to all parts of the burner. Atfits lower inner portion in the annular construction, the air 3. Engaging the upper wall of the air chamber' 2 and extending downward into the trough 3 is a blade or ring 4 which, with chamber is provided with an annular trough l whipped around the sharp edge. .The liquid fuel is introduced into the trough 3 alcove` the lower. edge of the blade and in being carried around the edge of the ring by v communication with the burner.

the rapidly moving air, is effectively broken up. The particular type of burner, embody ing the trough or cup, and the blade exten `ing into it, is not claimed in this application.

l'n Fig. 1 we have shown two pipes 12 and 13 for the introduction of fuel into the trough and these pipes may be used for the same fuel or one may be used for a light fuel and the other for a heavy fuel. rlhe light fuel is used for starting and after the burner becomes heated, the heavy fuel may be substituted. rlhe air and liquid fuel are fed'to the burner in substantially constant proportions and in the proper proportion to produce 4the proper combustion. Connected to the shaft of the air blower 24 are fuel measuring devices such as small plunger pumps 25 and 23 which are arranged in the fuel lines 12 and 13 respectively, and these devices vary the amount of fuel llowingin proportion to the speed of the blower. ihe lines 12 and 13 are provided with valves 27 and 28 for opening and closing the lines and these may be operated manually to shift from light fuel to heavy fuel when the, burner becomes hot. Automatic means may be employed when desired for shifting the fuel supply from light to heavy fuel and vice versa. Arranged in the lines 12 and 13 are valves 31 and 32 which are connected to a thermostatic device 33 which is in thermal The thermostat is so connnected to the valves 31 and 32 that the movement of the thermostat due to its increasing temperature, opens valve 32 and closes valve 31, thereby substituting the heavy fuel for the light fuel when the burner is hot. When the burner is cold, valve 31 is-open and valve 32 is closed.

After being whipped around -the sharp, lower edge of ring 4, the fuel mixture passes up through the annular mixing chamber 14, which is narrow and of small volume, so that the volume of explosive mixture present at any time is small and the liability of backfiring overcome. The upper edge ofthe ring4 lis provided with an inwardly and downwardly turned flange 15, which, with the flange 1G on the edge of the plate 7, forms a narrow, annular nozzlefroin which the Haine discharges toward the refractory material The llame is directed inward from the edge toward the center of the burner when the annular construction is employed. T he plate is provided -with a central aperture 17 through which the tire can be observed and ner-ieper.

through which additional air may be allowed to pass to complete the combustion, if it is necessary, a transparent damper 34 of mica orsimilar material being provided for that purpose.

After the burner has been in operation for a time,the plate 7 becomes heated and since the plate-forms one wall of the mixing chamber, the `cai'bureted mixture in the mixing chamber is heated and a more ellicient mixture is produced.

Means are provided for igniting the mixture at the nozzle.

other and are closer together than other insulated parts of the burner, so that when an E. lll. l?. is applied to the insulated parts,a sparkor plurality of sparks. discharge across the aperture of the nozzle and ignite the mixture. Since the nozzle is elongated the sparks jump across the aperture at did'erent parts of the nozzle and travel along the nozzle, thereby insuring instantaneous and complete ignition. Any suitable means, such as a spark coil 18 provided with a vibrator 19, may be employed in parallel with the motor 21 which drives the air blower for producing the necessary sparks, but when an electric motor is not employed for driving the blower, the ignition current may be derived from a storage battery.

ln the construction shown in Fig. 2, the burner is provided with two nozzles, 35 and 36,each ofsubstantially the same construction as the nozzle shown in Fig. 1, the nozzle 35 being arranged as the nozzle in Fig. 1 and the nozzle 36 being arranged at the center of the burner and being adapted to direct the llame outwardly toward the refractory material 8 which is so designed that the flame from either nozzle will not impinge on the other nozzle. ln this construction, the nozzle 36 is used for light fuel. the flame from which heats the burner to a sullicient degree before the fuel is started through the nozzle 35, and for this reason nozz`le36 only `has insulated parts across which the ignition spark jumps.

' ln the construction shown in Fig. 3 the fuel is fed through the shaft 37 onto the rotating disk 38 which is iovided with .vanes 39 on its under side. rranged below the disk is a circular element 41 which terminates adjacent the edge of the disk in an insulated ring 42 which is connected to one side of a sparking coil. Arranged above the periphery of the disk and adjacent thereto, is a stationary insulatedring 43 connected to the other side of the sparking coil. The oil fuel is thrown by the disk in a fine spray through the slotbetween the disk and the ring 43 and the air current issues from the slot between the disk and the ring 42 and the air atomizes the spray and produces an explosive mixture which is ignited by the spark The opposite sides or` ,walls of the nozzle are insulated from cach which jumps the gap 'between the insulated rin s 42 and 43 which form the nozzle.

e claim: i 1. In a liquid fuel burner, a nozzle formed of two parts electrically insulated from each other and forming the nozzleopen'ing, and

V means for causing an electric spark to bridge the nozzle opening.

2. In a liquid fuel burner, anozzle formed of two insulated plates spaced apart from each other, means for causing an electric sparkto bridge the gap between said plates, and means for blowing a,miXture o`f air and fuel through said nozzle, the mixture being adapted to be ignited by the' electric spark. 3. In a liquid fuel burner, a narrow, elongated nozzle formed of two parallel electrically insulated plates between which an igniting electric spark may be formed.

nozzle, said motor and spark terminals be-4 ing connected in par'allel,'whereby a pluvided when the motor circuit is closed.

In testimony whereof we haveA hereunto set our hands at San Francisco, California, this 15th day of March, 1917 l WILLIAM A. DOBLE.' WILLIAM A. DOBLE, JR. JOHN A. DOBLE. In presence of- I-I. G. PRosT.

rality of sparks across the nozzle are pro- 

